This invention relates to a distribution device for a system for the delivery of medical fluids to a patient. It also relates to a kit for injection of a contrast product into the human body.
This type of distribution device is in particular used in the course of diagnostic and therapeutic procedures in interventional radiology. In fact in this particular context doctors inject a contrast product into the patient's arteries or veins, checking the pressure of the artery into which the product is introduced from time to time. For this purpose the doctor creates a system for delivery of the contrast fluid to the patient using a set of flexible tubes connected to different tubes or channels in the distribution device.
In the course of these interventional radiology procedures it is frequently necessary to clean at least part of the distribution device, in particular the tube and the catheter attached thereto which delivers the contrast product to the patient, because of that fluid's tendency to set and deposit on the walls of the tube and the catheter after being immobile for some time. For this purpose the distribution devices incorporate a line known as a “rinsing” or “flush” line in which a saline solution or serum which is designed to carry off the contrast product previously used circulates under pressure.
A first type of distribution device appropriate for such an application comprises an assembly of at least two three-way taps mounted in series. Each of the taps comprises a separate manual control member.
In order that the contrast fluid may be injected, one of the channels of the first tap is connected by a line to the patient fitted with a catheter. The remaining channel of the same tap is connected to a pressure sensor connected to the flush line. A first channel of the second tap is connected to a reservoir of contrast product. A suction and injection syringe is connected to the second channel of the second tap.
The two taps make it possible to define two connection configurations between the various components of the system, these two configurations being used successively and repeatedly. In a first configuration the syringe is connected to the reservoir of contrast product while the pressure sensor is connected to the patient. In this first configuration contrast fluid may be drawn off by the doctor using the syringe and the flush liquid circulates to the patient. In the second configuration the bottle containing the contrast fluid, as well as the pressure sensor and the flush line, are isolated from the system, while the syringe is placed in communication with the patient. In this second configuration the doctor can inject contrast fluid into the patient. It will be understood that when using a distribution device comprising an assembly incorporating two three-way taps mounted in series the doctor will have to operate the two taps whenever he wishes to change the system between the two useful configurations. This manipulation is a source of error, in particular because the doctor may forget to operate one of the two taps. In addition to this the doctor must use both hands, one to hold the body of the taps and the other to operate the two controls for the taps in succession, rendering the operation relatively long.
A second type of distribution device suitable for the aforesaid application comprises a distributor incorporating a body which bounds internally a fluid circulation chamber into which there open an injection tube for the contrast medium, a pressure measurement tube connected to an arterial or venous pressure measurement line and a pressurised tube, sometimes called the “patient tube” connected to a line provided with a catheter to deliver the contrast fluid to the patient's artery or vein. Using a movable slide located within the chamber the doctor selectively connects the tube under pressure with either the injection tube or the pressure measuring tube. So that injection may be performed under sufficient pressure, the injection tube is connected to the distal extremity of a syringe body into which there opens a contrast fluid feed tube connected to a reservoir for that product. In order that at least the tube under pressure and the line connected thereto may be flushed, the flush line is connected to the pressure measuring tube and is provided with a closing member of the non-return valve type so that the flush solution can run through the tube under pressure connected to the patient when that tube is connected to the pressure tube via the slide chamber, by using a driving pump located in the flush line.
It will be understood that with such a distribution device the doctor must at the same time check that the movable slide within the chamber is in the correct position and that the pump driving the saline solution is correctly operating each time it is desired to flush the device.
Although this manipulation is simpler than that for a device having several taps, it remains difficult, in particular because the doctor may incorrectly adjust the flush fluid driving pump and thus disturb movements of the slide within the connecting chamber of the distributor. In addition to this manipulation of the pump is relatively time-consuming, particularly as it is not necessarily located close to the doctor, whose hands are holding the distribution device which has to be flushed.